1. Field
Various embodiments described herein relate to a connector, an optical transmission device, and a connector connection method.
2. Description of the Related Art
Signal connections between printed circuit boards and devices, performed through connectors using flexible printed circuit boards (Flexible Printed Circuits: FPC), have been widely prevalent in the mounting design of electronic devices.
Since the flexible printed circuit boards are printed circuit boards having flexibility, and the printed circuit boards can be bent or folded, the flexible printed circuit boards are heavily used for small products such as mobile phones, digital cameras, and the like in which mounting spaces are limited.
On the other hand, in electronic devices of recent years, the sizes and weight thereof and the thicknesses of devices have been rapidly reduced, and the miniaturization of semiconductor components and passive components has progressed. Therefore, high-density mounting has been requested.
In such a situation, connectors that connect the wirings of the printed circuit boards with the wirings of the flexible printed circuit boards have also been multi-pinned, and there has been an increasing need for the narrower pitch and the wider bandwidth of a connector unit.
As a technique of the related art, in Japanese Unexamined Patent Application Publication No. 2009-38250, a wiring circuit board is proposed that promotes the suppression of conduction noise. In addition, in Japanese Unexamined Patent Application Publication No. 2005-044769, a flat cable coupler is proposed that has a wider bandwidth. Furthermore, in Japanese Unexamined Patent Application Publication No. 2009-283901, a high-flex coverlay film is proposed that is used for a flexible printed circuit board. Furthermore, in addition, in Japanese Unexamined Patent Application Publication No. 2010-73786, a printed-wiring board is proposed whose conductor layer is disposed between a high-speed signal line and a resistor layer.
However, in a connector of the related art, there is a risk that, at the electrode portion of the connector connected to a GND passing between signal lines, a high-frequency characteristic possibly deteriorates owing to the occurrence of a noise, and there has been a problem that it is difficult to transmit a high-speed signal (for example, greater than or equal to 25 Gb/s) with high quality.